چکیده (انگلیسی):

Fasciolosis, amphistomosis and schistosomosis, transmitted by the freshwater snail species
Indoplanorbis and Lymnaea, are important snail-borne diseases in India as they affect the entire
spectrum of domestic animals causing substantial mortality and economic loss. Identifying any
heterogeneity in the spatial distribution of these snail-borne diseases will allow for targeted
disease control and efficient use of resources. The objectives of this study were threefold:
(i) to describe and explore the spatial distribution of Indoplanorbis and Lymnaea in Rohtak
and Jhajjar districts of Haryana, India (ii) to identify factors associated with occurrence of
these freshwater snail species and (iii) to produce a map showing the predicted risk of occurrence
of Lymnaea and Indoplanorbis spp. in the study area. Snails were collected from water
bodies of 99 settlements out of a total of 453 in the study area. Kernel smoothing was used
to generate a kernel ratio map while Kulldorff's spatial scan statistic was used to detect clusters
of settlements with a high/low risk. Multivariable logistic regression showed that snails were
almost ten times more likely to be present in rice-growing areas than in those not growing
rice (OR 9.24) and that snails were less likely to be present with each 1 km increase in distance
from a canal (OR 0.86). The regression model was used to produce a map illustrating the predicted
risk of snail occurrence. Since the distribution of vector snails mirrors the distribution of
snail-borne parasitic diseases, such spatial analysis helps to determine the relative risk of snailinfestation
as well as snail-borne diseases' distribution and planning of control activities.
© 2016 The Authors. Published by Elsevier Ltd on behalf of World Federation of Parasitologists.
This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/).